Speakers and Ohms: oh my!
 

Hello everybody,

I have a beautiful 2009 v70 D5 with High Performance Audio.

I really like music. I used to play drums. Back story over.

So I’m pretty sure I’ve trashed the standard speakers, mostly playing hip hop with the windows down. I am 47.

I tried to replace the speakers (with the help of Brad, my grease monkey cousin).

We took out the old speakers from the front, tweets and doors, and replaced with:

JBL STAGE 600 CE component speakers.

System Components · Nominal Output Power · Max Output Power · Frequency Response · Nominal Impedance · Sensitivity · Detachable Grilles
System Components2 speakers
Nominal Output Power50 Watt
Max Output Power150 Watt
Frequency Response50 ‑ 20000 Hz
Nominal Impedance4 Ohm
Sensitivity90 dB

I even added some soundproofing to the doors and behind the speaker etc.

It sounds awful.

I’ve searched and searched the forums and I do hate to ask but...

What have I done wrong here?

Is it ohms or sensitivity? Should I take out and replace with 2 ohms?

The head unit is standard as replacing that can be a headache, I have read, and I like the way it looks.

Any advice is greatly appreciated.... :_:

It wont be the ohms or sensitivity as such, that just alters the output per given amount of input, going 2 ohm would increase that.
Did you put the sound deadening etc in before listening, or as a posdible cure to the problem?
It could be the deadening thats causing the problem, or adding to it.
Car speakers arent in the same realm as domestic/professional boxed speakers. They're free air and use natural resonances and excessive 'enclosure' volumes as a benefit rather tgan a nuisance.
It might just be that the volume of the doors does not match the dynamics of the drivers, colouring and inhibiting the frequency response and reproduction.
Are they car speakers youve used? From the specs it does sound like they are.

The High Performance system uses 2 ohm speakers

Doubling the impedance to 4 ohm results in half the power
Half the power is 3dB
So unless the speakers are 3dB more efficient, you will have less maximum sound output with a 4 ohm instead of 2 ohm speaker

HOWEVER who listens at maximum power output?
A 4 ohm speaker means you just have to turn up the volume a bit more for the same loudness level

More likely the impact of the sound quality is caused by the type of speakers chosen and their matching to the enclosed space of the door and the car.

There's a lot more to car audio than just any old speaker in any old car....

Thanks For the reply, Andy.

Yes, we did install car speakers.

We have taken the speakers out of the doors and listened to them without the housing or mounts. They have the same issue on both sides.

They are very clear indeed at low volume. As soon as you push them to a reasonable ‘driving’ level of volume they start to distort. The woofer crackles and the tweeters crack and hiss.

I think it must be an exaggerated ohm issue, maybe I should try some 2ohm speakers or maybe replace with standards.

Also, in what way di they sound awful?
I know its difficult at times to express via text how something sounds, but any description might help.

Furthermore, theres a likelihood that the drivers volvo fitted were tuned to the door characteristics and those of the head unit too. Whilst they may not be the ultimate in performance, a generic and better quality driver may accentuate any negative characteristics that the originals were tuned to work around.

Thanks for the reply mate. And yes, it does seem a lot more complicated than I thought/hoped. :shocked:

I think, i’ll try and source some standard Volvo replacements or maybe some 2 ohm speakers would work well.

Ah, now, we might be onto something...
It may be that the speakers are being underdriven and the amp working harder for the required volume, and as such is reaching its limit and the sound is getting 'clipped' do you also hear some kind of 'popping' 'crackles' esp in complex/heavy sections?
2 ohm might indeed help this as youll ask less of the amp, providing the amp is happy running 2ohm.

Edit, yes you said woofer crackles and tweeters pop and hiss. Clipped signal, amp overloaded/beyond its working range.
The crackles, pops, etc are effectively 'holes' in the signal and a lack of residual current to supply the driver, emptying the capacitors etc which 'buffer' the current demands.

I am picking the speakers cannot handle the power output of the amplifier

Indeed, the speakers for the High Performance Audio are rated at 75W continuous power:
https://accessories.volvocars.com/en...CC-425452/2008

Interesting thanks, really appreciated. I couldn’t find that spec earlier for the life of me.

It says there that the factory speakers are 8 ohms, is that right?

Everywhere I have read it says that they are 2 ohms:confused_smile:

Ah ha, hang on. 4 drivers at 2 ohms each, right?